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pythontypesdatabricksassertionf-string

Output of type(object) not returned in Assert message (Databricks Python)

When applying the Python function type() to a single object, the type of the object is returned.

num = 5
type(num) 

Out[1]: int

When embedding this output into a string and printing the result, this seems to behave as expected.

num = 5
print(f"type of {num} is {type(num)}")

type of 5 is <class 'int'>

However, when using this exact message as an assertion error message, the type disappears from the message output.

num = 5
assert isinstance(num,str), f"type of {num} is {type(num)}"

AssertionError: type of 5 is

I am running the code through a notebook on a Databricks cluster, which is displayed in a web browser. The expected output would be: AssertionError: type of 5 is <class 'int'>.

What is the reason for this and how can it be avoided?

Edit: As mentioned by several commenters, the code works just fine running outside of the databricks environment. I have successfully verified this too using Python 3.10.6.

Solution

  • The character < in the output is being interpreted as the beginning of an HTML tag. By applying replace("<","&lt;") to the f-string, this can be avoided. The full code then becomes:

    num = 5
assert isinstance(num,str), f"type of {num} is {type(num)}".replace("<", "&lt;")